A near-eye display system comprises first and second optical waveguides. The first optical waveguide is configured to receive a first image through a first entry aperture, to expand the first image along the first optical waveguide, and to release an expanded first image. Layered parallel to the first optical waveguide, the second optical waveguide is configured to receive a second image through a second entry aperture, to expand the second image along the second optical waveguide, and to release an expanded second image to overlap the expanded first image. The second entry aperture is offset from the first entry aperture along the second optical waveguide.
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1. A near-eye display system comprising:
a first optical waveguide configured to receive a first component image through a first entry aperture, to expand the first component image along the first optical waveguide, and to release an expanded first component image; and
layered parallel to the first optical waveguide, a second optical waveguide configured to receive a second component image through a second entry aperture, to expand the second component image along the second optical waveguide, and to release an expanded second component image to an area overlapping the expanded first component image, such that the first and second component images form a fused display image in a field of view of a wearer of the near-eye display system, the second entry aperture being offset from the first entry aperture along the second optical waveguide.
12. A near-eye display system comprising:
a first optical waveguide configured to receive a first-color component image through a first entry aperture, to expand the first-color component image along the first optical waveguide, and to release an expanded first-color component image; and
layered parallel to the first optical waveguide, a second optical waveguide configured to receive a second-color component image through a second entry aperture, to expand the second-color component image along the second optical waveguide, and to release an expanded second-color component image to an area overlapping the expanded first-color component image, such that the first- and second-color component images form a fused color display image in a field of view of a wearer of the near-eye display system, the second entry aperture being offset from the first entry aperture along the second optical waveguide.
16. A near-eye display system comprising:
a reflective image-forming array;
a first light-emitter configured to direct emission onto the reflective image-forming array at a first angle, to form a first component image;
a second light-emitter configured to direct emission onto the reflective image-forming array at a second angle, to form a second component image;
a first optical waveguide configured to receive the first component image through a first entry aperture, to expand the first component image along the first optical waveguide, and to release an expanded first component image;
layered parallel to the first optical waveguide, a second optical waveguide configured to receive a second component image through a second entry aperture, to expand the second component image along the second optical waveguide, and to release an expanded second component image to an area overlapping the expanded first component image, such that the first and second component images form a fused display image in a field of view of a wearer of the near-eye display system, the second entry aperture being offset from the first entry aperture along the second optical waveguide; and
a consolidation optic configured to receive the first and second component images, to direct the first component image into the first entry aperture, and to direct the second component image into the second entry aperture.
2. The near-eye display system of
3. The near-eye display system of
4. The near-eye display system of
5. The near-eye display system of
6. The near-eye display system of
7. The near-eye display system of
8. The near-eye display system of
9. The near-eye display system of
10. The near-eye display system of
a reflective image-forming array;
a green light emitter configured to direct emission onto the reflective image-forming array at a first angle, to form the first component image;
a blue light emitter configured to direct emission onto the reflective image-forming array at a second angle, to form the second component image; and
a consolidation optic configured to receive the first and second component images, to direct the first component image into the first entry aperture, and to direct the second component image into the second entry aperture.
11. The near-eye display system of
13. The near-eye display system of
14. The near-eye display system of
15. The near-eye display system of
a reflective image-forming array;
a first light emitter configured to direct emission of a first color onto the reflective image-forming array at a first angle, to form the first-color component image;
a second light emitter configured to direct emission of a second color onto the reflective image-forming array at a second angle, to form the second-color component image; and
a consolidation optic configured to receive the first- and second-color component images, to direct the first-color component image into the first entry aperture, and to direct the second-color component image into the second entry aperture.
17. The near-eye display system of
19. The near-eye display system of
20. The near-eye display system of
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In recent years, near-eye display technology has transitioned from niche status into an emerging consumer technology. Implemented primarily in head-worn display devices, near-eye display technology enables 3D stereo vision and virtual reality (VR) presentation. When implemented with see-through optics, it enables a mixed reality, in which VR elements are admixed into the user's natural field of view. Despite these benefits, near-eye display technology faces numerous technical challenges not encountered in conventional display technology. These include the challenge of projecting right- and left-eye display images into a sufficiently wide eye box while preserving display image quality.
One embodiment is directed to near-eye display system comprising first and second optical waveguides. The first optical waveguide is configured to receive a first image through a first entry aperture, to expand the first image along the first optical waveguide, and to release an expanded first image. Layered parallel to the first optical waveguide, the second optical waveguide is configured to receive a second image through a second entry aperture, to expand the second image along the second optical waveguide, and to release an expanded second image to overlap the expanded first image. To reduce cross-coupling of the first and second images, the second entry aperture is offset from the first entry aperture.
This Summary is provided to introduce in a simplified form a selection of concepts that are further described in the Detailed Description below. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.
Aspects of this disclosure will now be described by example and with reference to the drawing figures listed above. Components, process steps, and other elements that may be substantially the same in one or more of the figures are identified coordinately and are described with minimal repetition. It will be noted, however, that elements identified coordinately may also differ to some degree. Except where particularly noted, the figures are schematic and generally not drawn to scale. Rather, the various drawing scales, aspect ratios, and numbers of components shown in the drawings may be purposely distorted to make certain features or relationships easier to see.
Some display-systems include a plurality of reflective image-forming arrays-separate arrays for red, green, and blue component images. In these configurations, a composite color image is formed by downstream optical fusion of the component images. In the embodiment of
Accordingly, first light emitter 26R of
Images 14 as produced by image-forming array 24 are typically not suitable for direct viewing by the user of HMD device 10. Image-forming array 24 offers a very small exit pupil that would have to be aligned to within a millimeter of the user's anatomical pupil for proper viewing. Even then, the user may perceive vignetting of the sighted image under dark conditions, when the anatomical pupil could be larger than the exit pupil of the image-forming array. Accordingly, near-eye display system 12 includes a pupil expansion portion 30 configured to expand the component images from image-forming array 24 across an area in which the user's pupils are likely to be situated. The pupil expansion portion includes a stack of optical waveguides 32, each waveguide having an entry aperture 34 as well as an exit pupil (vide infra).
First waveguide 32R is configured to receive a first image 14R through first entry aperture 34R, to expand the first image along the length of the first waveguide, and to release an expanded first image 36R. Layered parallel to the first waveguide, second waveguide 32G is configured to receive a second image 14G through a second entry aperture 34G, to expand the second image along the length of the second waveguide, and to release an expanded second image 36G to overlap the expanded first image. Third waveguide 32B is layered parallel to the first and second waveguides. The third waveguide is configured to receive a third image 14B through third entry aperture 34B, to expand the third image along the length of the third waveguide, and to release an expanded third image 36B to overlap the expanded first and second images.
In the embodiment of
Due to the layered arrangement of waveguides 32 in near-eye display system 12, second waveguide 32G must transmit first image 14R and third image 14B to first waveguide 32R and to third waveguide 32B, respectively, in order for the first and third images to be received in their respective entry apertures. Likewise, third waveguide 32B must transmit the first image to the first waveguide. Moreover, expanded second image 36G must be transmitted by the first and third waveguides to the user's eye, and expanded third image 36B must be transmitted by the first waveguide. The illustrated stacking order of the first, second, and third waveguides in expansion portion 30 should not be construed as limiting in any way. Naturally, the various permutations in the stacking order would give rise to different requirements for transmission of the expanded and non-expanded component images.
Ideally, light outside of the narrow wavelength band and acceptance cone of entry aperture 34 does not strongly interact with the entry aperture, but primarily passes directly through the associated waveguide 32. In some implementations, therefore, entry apertures of the waveguides that expand the component images of the different colors may be aligned along the length of the layered waveguides. This configuration may help to minimize the footprint of a near-eye display system. It is observed, however, that even a small amount of light of an unexpected wavelength may have undesired consequences when coupled into another pupil-expanding waveguide. Such consequences include ‘ghost’ images and display-color impurity.
To address these issues, second entry aperture 34G in
In a layered waveguide configuration, a component image 14 may be directed to its intended entry aperture 34 by controlling the angle at which that component emerges from image-forming array 24. Returning again to
The manner of directing emission onto image-forming array 24 at different angles is not particularly limited. In the embodiment shown in
No aspect of the foregoing drawings or description should be understood in a limiting sense, for numerous variations, extensions, and omissions are contemplated as well. For instance, the pupil expansion solution as described above operates largely in one dimension—typically in the horizontal direction across the user's field of view. For implementations in which vertical pupil expansion is also desired, the above solution may be applied redundantly—i.e., vertical followed by horizontal expansion, or vice versa. Alternatively, any given waveguide 32 of pupil-expanding portion 30 may be configured to expand a component image 14 in two orthogonal directions (i.e., to provide concurrent horizontal and vertical pupil expansion.
In waveguide 32′ of
In pupil-expanding portions having waveguides like that of
While the above description relates primarily to pupil expansion of component images of different colors, this aspect is by no means necessary. The layered waveguide approach described above can also be applied to component images of the same color. The motivation in that case may be to direct intense image light through different optical channels, so as to avoid overheating any one channel. Thus, the various component images referenced above may be substantially identical in some implementations.
One aspect of this disclosure is directed to a near-eye display system comprising first and second optical waveguides. The first optical waveguide is configured to receive a first image through a first entry aperture, to expand the first image along the first optical waveguide, and to release an expanded first image. Layered parallel to the first optical waveguide, the second optical waveguide is configured to receive a second image through a second entry aperture, to expand the second image along the second optical waveguide, and to release an expanded second image to overlap the expanded first image, the second entry aperture being offset from the first entry aperture along the second optical waveguide.
In some implementations, each of the first and second entry apertures includes a surface-relief grating. In some implementations, each of the first and second entry apertures includes one or more of a volume hologram and a polarization Bragg grating. In some implementations, the near-eye display system further comprises an exit pupil arranged on the each of the first and second optical waveguides, wherein the exit pupil of first optical waveguide is configured to release the expanded first image, and the exit pupil of the second optical waveguide is configured to release the expanded second image. In some implementations, the second optical waveguide is further configured to transmit the first image through to the first optical waveguide. In some implementations, the near-eye display system further comprises a third optical waveguide layered parallel to the first and second optical waveguides, wherein the third optical waveguide is configured to receive a third image through a third entry aperture, to expand the third image along the third optical waveguide, and to release an expanded third image to overlap the expanded first and second images. In some implementations, the third entry aperture is aligned to the first or second entry aperture. In some implementations, the third entry aperture is offset from both the first and second entry apertures along the third optical waveguide. In some implementations, the first and second entry apertures are offset along a first axis, and the first and third entry apertures are offset along a second axis. In some implementations, the near-eye display system further comprises a reflective image-forming array; a first light emitter configured to direct emission onto the reflective image-forming array at a first angle, to form the first image; a second light emitter configured to direct emission onto the reflective image-forming array at a second angle, to form the second image; and a consolidation optic configured to receive the first and second images, to direct the first image into the first entry aperture, and to direct the second image into the second entry aperture. In some implementations, each of the first and second emitters includes a laser or light-emitting diode.
Another aspect of this disclosure is directed to a near-eye display system comprising first and second optical waveguides. The first optical waveguide is configured to receive a first image of a first color through a first entry aperture, to expand the first image along the first optical waveguide, and to release an expanded first image. Layered parallel to the first optical waveguide, the second optical waveguide is configured to receive a second image of a second color through a second entry aperture, to expand the second image along the second optical waveguide, and to release an expanded second image to overlap the expanded first image, the second entry aperture being offset from the first entry aperture along the second optical waveguide.
In some implementations, the near-eye display system further comprises a third optical waveguide layered parallel to the first and second optical waveguides, wherein the third optical waveguide is configured to receive a third image of a third color through a third entry aperture, to expand the third image along the third optical waveguide, and to release an expanded third image to overlap the expanded first and second images. In some implementations, a median wavelength of the second color lies between a median wavelength of the first color and a median wavelength of the third color, and wherein the third entry aperture is aligned to the first or second entry aperture. In some implementations, the near-eye display system further comprises a reflective image-forming array; a first light emitter configured to direct emission of the first color onto the reflective image-forming array at a first angle, to form the first image; a second light emitter configured to direct emission of the second color onto the reflective image-forming array at a second angle, to form the second image; and a consolidation optic configured to receive the first and second images, to direct the first image into the first entry aperture, and to direct the second image into the second entry aperture.
Another aspect of this disclosure is directed to a near-eye display system comprising first and second optical waveguides, a reflective image-forming array, first and second light emitters, and a consolidation optic. The first optical waveguide is configured to receive a first image through a first entry aperture, to expand the first image along the first optical waveguide, and to release an expanded first image. Layered parallel to the first optical waveguide, the second optical waveguide is configured to receive a second image through a second entry aperture, to expand the second image along the second optical waveguide, and to release an expanded second image to overlap the expanded first image, the second entry aperture being offset from the first entry aperture along the second optical waveguide. The first light-emitter is configured to direct emission onto the reflective image-forming array at a first angle, to form the first image. The second light-emitter is configured to direct emission onto the reflective image-forming array at a second angle, to form the second image. The consolidation optic is configured to receive the first and second images, to direct the first image into the first entry aperture, and to direct the second image into the second entry aperture.
In some implementations, each of the first and second light emitters includes a light emitting diode, a collection lens optically downstream of the light-emitting diode, and a microlens array optically downstream of the collection lens, wherein the microlens array is configured to image the emission of the light-emitting diode onto the reflective image-forming array. In some implementations, the first and second angles are coplanar. In some implementations, the first and second angles lie in different planes. In some implementations, the reflective image-forming array is a liquid-crystal-on-silicon (LCOS) array.
It will be understood that the configurations and/or approaches described herein are exemplary in nature, and that these specific implementations or examples are not to be considered in a limiting sense, because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, various acts illustrated and/or described may be performed in the sequence illustrated and/or described, in other sequences, in parallel, or omitted. Likewise, the order of the above-described processes may be changed.
The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, and other features, functions, acts, and/or properties disclosed herein, as well as any and all equivalents thereof.
Patent | Priority | Assignee | Title |
10725291, | Oct 15 2018 | META PLATFORMS TECHNOLOGIES, LLC | Waveguide including volume Bragg gratings |
10775626, | May 16 2019 | Rockwell Collins, Inc. | Wide field of view head worn display device |
11143866, | Oct 15 2018 | META PLATFORMS TECHNOLOGIES, LLC | Waveguide including volume Bragg gratings |
Patent | Priority | Assignee | Title |
6788388, | Oct 22 1998 | ASML NETHERLANDS B V | Illumination device for projection system and method for fabricating |
20020093521, | |||
20030086624, | |||
20040130762, | |||
20060078125, | |||
20070177275, | |||
20090185153, | |||
20100141902, | |||
20120113306, | |||
20130250430, | |||
20140104665, | |||
20140140653, | |||
20160085300, | |||
20180082644, | |||
WO2016118367, |
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